860 DSP & 860 DSPi - Operation Manual, Section I: The Basics 1.40 Introduction The 860 DSPi has two standard features which enhance communication security, the Secure860Lin k (S8L), and the Instrument Fingerprint. The S8L enhances privacy for communicat ions between the meter and the T rilithic Data Manager (TDM) system. The Instrument Fingerprint system will be discussed in the next chapter. 9 SSL Certificate The S8L feature in the 860 DSP and 860 DSPi uses a unique 1024 bit RSA certificate on every 860 in the cable system and utilizes Secure Sockets Layer (SSL) encryption. Note: The TDM must also have this feature i nstalled for the Secure860Link to work. Note: The TDM maintains a list of the connection attempts made by unauthorized 860 meters. The TDM administrator may authorize or de-authorize a meter at any time. 9. Secure860Link Upon initial activation of the S8L Mode, the meter will (on the next reboot) create a self signed SSL certificate identifying the meter by its MAC address. This may take up to 5 minutes to create but must be done only once. After this certificate is created and its private key stored in the hidden flash memory, the certificate will be loaded into the run-time memory for use by the meter’s internal web server and internal web browser. The meter operator (using the Web Browser Menu) logs into the TDM using the secure web port 443 (https:// link) and causes the TDM to establish a data connection back to the meter over port 443. The TDM then requests the meter ’s SSL certificate and compares it against authorized meters within its database. If the meter is authorized, communication continues over port 443 until the transactions are completed. If the meter is not approved in the database, then communication is halted by the TDM.